Diarrhoea

Diarrhea is defined as frequent, loose and watery stools. There are two types of diarrhoea, rapid onset (acute) and gradual onset (chronic).

ACUTE
This is defined as diarrhoea of rapid onset, that lasts less than three weeks. However, it usually lasts less than one or two days. This usually goes away without the need for treatment.
Many types of bacteria consumed through contaminated food or water can cause diarrhea. Common culprits include Campylobacter, Salmonella, Shigella, Escherichia coli (E. coli) and Cloistridium difficile.
Certain viruses, including rotavirus, Norwalk virus, cytomegalovirus, herpes simplex virus and viral hepatitis, also cause diarrhea. Rotavirus is the most common agent in diarrhoea affecting children,
Parasites that cause diarrhea include Entamoeba histolytica, Giardia lamblia and Cryptosporidium.

CHRONIC
Chronic diarrhoea is usually related to functional disorders

Symptoms
Abdominal pain, bloating, nausea often accompany diarrhoea. Fever may be present, and diarrhoea may result in sorenesss of the skin around the anus. Dark and unusually smelling stools, high fever and signs of dehydration may indicate or cause more serious disease and medical help must be sought. Signs to watch for include thirst, decreased urination, darker urine, dry skin, feeling of faint and/or fatigue.
In children signs to watch out for include dry mucous membranes (dry mouth), no tears when crying, no wet diapers for 3 hours or more, irritability, sunken eyes, sunken cheeks, fever, listlessness and decreased skin turgour (doesn't flatten when pressed).

Diagnosis
The physician may ask the patient questions about the nature of symptoms, when they first came on, what food has been consumed, medication they have been using (such as antibiotics or antacids), any co-morbidities.Unless the patient has a high fever, bloody diarrhoea or or diarrhoea lasting more than 4-5 days, no investigations are required.
Blood tests may indicate an infectious cause of the diarrhoea and ruling out other possible causes.
A sample of stool may be taken and sent to a laboratory for analysis. There it is cultured (placed in conditions where organisms are allowed to grow) to check for bacteria or parasites. Faecal leukocytes (white blood cells) may also be detected, indicating inflammation.
Colonoscopy or sigmoidoscopy may be performed in order to visualise the lining of the colon and rectum. This involves advancing a lighted instrument (sigmoidoscope or colonoscope) into the colon. In the case of the colonoscope, an image is transmitted onto a screen, allowing abnormalities to be detected.
If lactose intolerance, allergy or coeliac sprue is suspected to be causing the diarrhea, the physician may advise the patient to avoid certain foods to see if the diarrhoea responds.

Treatment
• Acute
Most cases of acute diarrhoea do not require treatment. However, prevention of dehydration is important in all cases. Replacing of lost fluid is imperative as dehydration can lead to serious problems. Water alone is not enough to replenish body fluids as it does not contain electrolytes. Fruit juices and soup contain electrolytes and must be given too. If fluids cannot be given orally (due to unconsciousness for example), they must be given intravenously.
The majority of acute diarrhoea is caused by bacteria or parasites, and the diarrhoea functions to remove the infectious organisms from the body. If it is viral or non-infectious, anti-diarrhoeal medication such as loperamide and bismuth salicylate may prove helpful. If these are
Antibiotics may be prescribed if there is evidence of systemic infection such as fever, chillds, malaise.
Certain foods including fatty or sugary foods, dairy products and fibre tend to worsen the symptoms of diarrhoea and should be avoid ed until recovery.

• Chronic
The treatment of chronic diarrhoea is based on identification of the underlying cause and appropriate treatment. Anti-diarrhoeal agents often prove useful.

To avoid diarrhoea when travelling
Do not consume:
• Tap water or ice made from it; do not brush your teeth with it;
• Use bottled water only
• Raw fruits and vegetables unless they can be peeled and you peel them yourself.
• Raw, reheated cold or rare meat or fish, as all of these may be contaminated with infectious bacteria, viruses or parasites.

Malabsorbtion conditions such as cystic fibrosis, lactose intolerance, coeliac sprue, bacterial overgrowth or inflammatory bowel disease can cause diarrhoea. Factors which increase motility such as thyrotoxicosis may cause diarrhoea.
Tumours such as Zollinger-Ellison syndrome, colorectal cancer, carcinoid syndrome and VIPomas may also result in diarrhoea.

Medication
Antibiotics may kill the natural harmless bacteria found in the colon, allowing a harmful bacteria called Cloistridium difficile to grow in its place. Certain medications such as chemotherapy and magnesium antacids can cause diarrhoea as a side effect.